Gas-engine



- (NoModeL'f) v ZSheets-Sheet 1.

F. P. MILLER. GAS ENGINE.

No. 532,980. Patented Jan. 22, 1.895.

P. P'. MILLER.

GAS ENGINE.

l f (N0 MGdeI- .2 shets-sneec 2. i

N- 532,980- Patented Jan. 22, 1895.

' FRANKLIN P. MILLER, OF BLOOMFIELD, NEV JERSEY.

GAS-ENGINE.

SPECIFICATION forming part of Letters Patent No. 532,980, dated January 22, 1895.

Application lilcd February l2, 1894. Serial No. 499.94% (No model.)

To @ZZ whom tv may concern.-

Beit known that I, FRANKLIN P. MILLER, a citizen of the United States, residing at Bloomfield, in the county of Essex and State of New Jersey, have invented new and useful Improvementsin Gas-Engines, of which the following is a specification.

My invention relates to that class of gas engines commonly known as four cycle engines, wherein acomplete working cycle is `composed of four strokes of the piston, a mixture of gas and air being drawn into the cylinder by suction, compressed, ignited, and the waste products of combustion finally eX- pelled. In engines of this class these operations t'ake place in the manner andorder following: The irst outward stroke of the piston draws into the cylinder a charge of air and gas mixed in the proper proportions to be highly explosive. The second or inward movement of the piston compresses the mixture of gas and air, and at the end of this stroke, while the compression is greatest,the mixture is ignited,.and the piston propelled outward on its third stroke. On the fourth or inward stroke of the piston the waste products of combustion are expelled from the cylinder into a suitable receptacle.

The objects of the present invention are to provide an improved governor and valve connections for regulating the speed of the engine and to provide an improved igniting device.

To these ends my invention consists in the novel construction, combination, and arrangement of parts hereinafter fully described and afterward definitely pointed out in the claims following the description, due reference being had to the accompanying drawings form. ing a part of this specification, wherein` Figure l is a side elevation of my improved engine. Fig. 2 is an enlarged view showing a longitudinal, Vertical section through the valve chest, and a side elevation of the governor, the disk supporting the governor balls being removed' for the sake of clearness. Fig. 3 is an end 'elevation of the governor. Fig. 4 is asectional view of the cylinder, valve chest and igniting device.

Referring to the drawings the letter A indicates the bed of the engine; B, the cylinder; C, the valve chest; D, the piston rod, and E the crank shaft.

The valve chest C is located at oneside of and near the rear end of the cylinder B, as shown, and communicates with said cylinder by the inlet port c and exhaust port c. A gas inlet c2 communicates with the port c by meansvof an annular passage c3, and anair inlet c4 also communicates with said port by means of an annular passage c5, concentric with the passage c3. The passages c3 and c5 are closed by valve F provided with a stem f which projects downwardly through the valve chest, and at its lower end is provided with a stirrup f', for the purpose hereinfater described. About said stem and between the top of said stirrup and the bottom of the valve chest is arranged a coiled spring f2 which operates to close the valve F. The exhaust port c is also controlled by a valve G provided with a stein g which projects downwardly through the valve chest and at its lower end is encircled by a coiled spring g which vbears against the bottom of the valve chest and against an adjusting lnut g2, and operates to close said valve. To a hanger l) is pivoted a double bell crank lever H, one arm h of which bears againstthe under side of the stein g of the exhaust valve, and the other arm h is adapted to rest within the stirrup f. The lower end of said stirrup is provided with a cylindrical aperture within which is seated a button f3 held up against a shoulder]c4 by a coiled springfs, the tension of said spring being adjusted by a screw-plug ff fitted in the lower end of the stirrup. The arm h of the bell crank H bears against said button, and by rocking said bell crank about its pivot the valves F and G are alternately operated in the manner presently to be described. Upon the crank shaft E is keyed a gear wheel c which meshes with a gear wheel I journaled to the engine frame, the ratio of said wheels being as one to two. Upon the hub of the wheel Iis formed a cam which is adapted to engage a rollerj journaled to the upper end of a rock` arm J. A connecting rod h2 is pivoted at one end to said rock-arm and 'at its other end is pivoted to the bell-crank H. To the end of the crank-shaft E is secured a disk or plate K, to which, at opposite points, are

ICO

pivoted arms 7;, Za', carrying governor balls 7e?. The arm Zr is pivoted to said disk at a point between its ends, as shown, while the arm Za is pivoted at its extreme end, said arms being connected as shown by alink k3 to cause them to move in unison. One of the arms, as 7c, is provided upon its outer -side with a cam Zr", for the purpose to be presently made appar- .ent. To each of the governor balls is connected one end of a coiled spring R5, the other ends of said springs being attached to the plate or disk K. The springs serve to draw the governor balls toward the center of the disk K in the well4 known manner. To the rock arm .I is pivoted a bell-crank lever Z which is pivotally secured to one end of a lever Z, which at its other end is pivoted to the engine frame, the levers Z, Z', forming a togglelever L3. From the upper arm Z2 of the lever Z projects an arm Z3, to the end ot' which is attached one end of a coiled spring Z4, the other end of said spring being secured to the rock arm J.

As thus described the operation of the device is asfollows: Upon the first or outward stroke of the piston, a partial vacuum is formed behind the piston, raising what I denominate the mixing valve F and drawing in a charge of mixed gas and air. Upon the return stroke of the piston the valve F closes by the combined action of gravity, the spring f2 and the pressure exerted by the piston, and the mixture is compressed. At the extreme end of the stroke the mixture is ignited, as will hereinafter be described, propelling the piston outward. During these three strokes ofthe piston the crank-shaft has made one and one-half revolutions thus revolving the gear wheel I three quarters of a revolution. At this point the piston starts inward upon its fourth stroke, and at the same moment the cam i abuts against the roller j journaled in the upper end of the rock arm J and forces said arm to one side, which, through the medium of the rod h2, rocks the bell crank lever II upon its pivot and causes the arm Zt to raise the exhaust valve G. The cam lforming onefourth of the periphery of the wheel I, and said wheel making one revolution to every two revolutions of the wheel e, or four strokes of the piston, it will be seen that the exhaust valve G is held open during the entire period of the fourth stroke of the piston, thus permitting the waste products of combustion to be expelled from the cylinder into a suitable exhaust chamber or receptacle. At the completion of the'fourth stroke ofthe piston the cam 1I leaves the rollerj, when the spring g will immediately close the exhaust valve G and simultaneously rock the bell-crank H and draw back the rock arm J' to its original position. Should the momentum of the engine become loo great the governor balls 7.52 will be thrown outward by centrifugal force,causin g the cam Zr", on the governor' arm k, to strike the upper end of the arm Z2 of rthe toggle lever L, forcing said toggle lever over to the opposite side of its center, and before the springr Z4 can draw it back to its former position the cam i will have left the rollerj and the spring g will start to close the exhaust valve G. This action ofthe springg, however, will draw the rock-arm .I toward the hub of the wheel I, thus forcing the lower arm ot bell-crank, arm Z ot which forms one arm ofthe toggle lever L against a pin M on the rock arm, arresting the further movement ofthe latter and preventing the closing of the exhaust valve G. Al though the spring Z1 tends to return the parts to normal position, it will be understood that the pressure of the spring g acting through the medium ot' the bell-crank II, the rod h2,

the rock-armLand the toggle-lever L, will` maintain the said `toggle-lever in its locking position, thereby holding the exhaust-valve open duringexcessive speed ot the engine, for, in order to close the exhaustvalve, when the toggle rests against the pin M, it will be necessary to force the toggle against the p ressure of the spring g to the other side ofthe center, thus forcing the rock-arm from the' hub ofthe gear I to a Adistance equal to the distance it is forced by the cam z', the spring Z4 having only tension enough to draw the tog gie-lever L past the center when released from its locked position by reason of the cam i forcing the rock-arm .T away from the hub of the gear I., The pin M- is so situated as to allow the rock-arm'J to move a short distance toward the hub of the gear I after the cam has left the rollj. The exhaust valve is thus held open and at the same time the arm 7L ot the bell crank II holds down the mixing valve F to its seat. The piston will new, on its outward stroke, draw into the cylinder through the exhaust valve the burned or waste gases, upon its next stroke will expel the same through the exhaust, upon its next outward stroke will again draw in the burned or waste gases, and will again expel them, the mixing valve F being all this time held closed and the exhaust valve G heldopen. The valves will be held in this position until released by the cam t' again rocking the arm J away from the hub ot the wheel I, upon which the spring Z4 will immediately swing the toggle lever L back past its center to its original position, and it the speed of the engine has slackened sufficiently to permit the governor balls being drawn inward by their springs so that the cam ZcL will clear the arm Z2 of the toggle le-4 ver, the piston will upon its next stroke again draw in through the mixing valve F a fresh charge ot' gas and air.

It will be understood that when the exhaust valve is held closed by its spring the arm Z2 of the toggle lever will be held away from and outI of the path 0E the cam le, and this is cssential, as the exhaust valve must open but once during every two revolutions of the disk carrying the governor balls.

In practice the pivot connecting the levers Zand Z of the toggle L will be allowed a little play so as to allow the toggle to pass from one IOO side of the center to a correspondingdistance to the other side without raising the roll from the cam t', so that the cam 104 will by slight pressure force the toggle L into its lowerposition, and said cam h4 is made long enough to hold it in this position until the cam t' has left the rollerj, when the arm Z of the toggle will settle against the pin M, as before described.

N indicates the igniting device, constructed as follows: 'lo the side and near the rear end of the valve chest C is formed a casing n which communicates by means ot' apassage n with the gas and air inlet of the cylinder. Said casing is cored out centrally, as shown, and is internally screw-threaded for the reception of a screw-threaded plug O which seats itself against a shoulder o at its top, and at .its bottom tightly fits the cored out casing, thus forming gas tight joints at these points.. Said plug is provided with a port o which registers withthe passage n in-the casing n when the plug O is screwed up in place. In said port is fitted a vertical tube P which is closed at its upper end, and in the upper end of the cored out casing n is fitteda vertically adjustable sleeve n2,'held in its adjusted position by means of a set-screw 'n3 tapped through the upper end of the casing. Fitted over the upper end of the casing n is a chimney N which projects for a suitable distance above the top of the igniting tube P. The chimney N', at a point just above the top of the casing n, is provided with a series of perforations fn, which serve as air inlets to support combustion, as hereinafter made apparent. The casing n is provided with a nipple n within which is fitted 'a tube q having at its end a cap Q which is provided with air inlets q and an inlet q2 for the admission ot gas in the same manner as a Bunsen burner.

The operation of the igniting device is as follows: Gas and air are supplied to the burner through the tube q and pass up about the igniting tube until the top of the sleeve n2 is ,reached at which point ignition takes place and heats the igniting tube. Before reaching this point the supply of air is insufcient to support combustion, which cannot occur until the mixed gas and air escape from the sleeve n2, at which point air issupplied through the perforations /rtfin t-he base of the chimney N. Upon starting the engine the tube P is filled with air or the burned gases of a previous charge. The first stroke of the pistonvfills the cylinder with a combustible mixture of gas and air. The second or inward stroke compresses the charge so as to occupy, say, one-third of its volume at atmospheric pressure when the piston has reached the end of its stroke. The old gas in the tube will now'be forced to occupy onethird the space, and being followed up by the combustible mixture the junction of the' burned and'combustlble gas will just reach the heated part of the tube causing the ignition of the combustible gas. The point at f ing in bursting the jackets.

which the ignition takes place may be regulated by raising or lowering the sleeve n2, so as to causethe ignition to take place at the 'moment the piston reaches the end of itsinniting tube removably therein, the plug may be quickly taken out in case the igniting tube burns out,'and another plug fitted with au iglniting tube substituted, when the damaged tube may be removed from the plug at leisure.

The cylinder and valve chest, as usual, are provided with water jackets R, r, to prevent overheating.` Heretofore much trouble has beeu'experienced from the water in the jackets freezing in very cold weather, often result- I cut an .aperture through the jacket, as at R and secure over said aperture, by bolts or other suitable fastenings, a metallic plate S which is thinneror weaker than the jacket R, so that-in the event of the water in the jacket freezing the plate will break and permit the escape of the water. As shown the aperturev is made in the bottom of the cylinder. Should it be made in the top the water would freeze on the top first and become firmly wedged to the sides of the cylinder,- and as the remaining water froze it would be apt to burst the bottom ot the cylinder.

Having described' my invention, what I claim is 1. In a gas engine, the combination with the inlet and exhaust valves and springs for closing them, of a double bell crank operating to open the exhaust valve and hold the inlet valve closed,` a rock-arm, a connection bctween said bell crank and rock arm, mechanism for periodically vibrating said rock arm, a toggle lever fixed at one end and at its other end pivoted to the rock arm, a spring for throwing said toggle lever in one direction, a' pin on the rock arm to arrest the motion of the toggle lever in the opposite direction, and a speed governor provided with means for throwingthe toggle lever against said pin, substantially as described, and for the purpose specified. l

2. In a gas engine, the combination with the inlet-and exhaust valves and springs for closing them, of a double bell crank operating to open the exhaust valve and hold the inlet valve closed, a rock arm, a connection between said bell crank and rock arm, a cam wheel for vibrating the rock arm, a governor comprising pivoted, weighted arms, a cam carried by one of said arms, a toggle-lever fixed at one end and at its other end pivoted to the rock-arm and provided with an arm adapted to be engaged by said cam, a spring for'moving the toggle lever in one direction, and a pin on the rock arm for arresting the movement of the toggle lever in the other direction, substantially as described.

3. In a gas engine,'the combination with the To prevent this ICO inlet and exhaust valves and springs for closing them, of the stirrupf carried by the inlet valve, said stirrup being centrally apertured as shown and provided with a shoulder-f4, the button f3 arranged in said aperture and abutting against said shoulder, a spring arranged below said button, a screw plugf6 for adjusting the tension of said spring, a double bell crank one arm of which is adapted to bear against said button and the other end against l, the under side of the exhaust valve, and

means for automatically rocking said bell crank to open the exhaust valve and close the inlet valve, substantially as described.

4. An igniting device for gas engines, comprising a hollow casing having arranged therein a tube closed at one end and cummunicating at its other end with the cylinder. a gas supply for said casing, and aivertically adjustable sleeve surrounding said tube, substantially as described and for the purpose specified.

5. An igniting device for gas engines, comprising a hollow casinghavng arranged therein a tube closed at one end and communicating at its other end With the cylinder, a gas supply for said casing, a vertically adjustable sleeve surrounding said tube, and a chimney perforated near its base 'and fitted over said tube and sleeve, substantiallyas described.

6. An igniting device for gas engines, comprising a hollow casing having removably fitted therein a plug carrying a detachable igniting tube closed at one end and at its other end communicating with the cylinder, an adjustablesleeve surrounding said tube, and a gas supply for said casing, substantially as described.

7. In an igniting device for gas engines, the combination with a casing 'n provided with the passage fn', of the screw-plug O fitted in the bottom of said casing and seated against a shoulder o, the port o in said plug registering with the passage n', the igniting tube P closed at its upper end and removably fitted in said plug, an adjustable sleeve n2 surrounding said tube, and a gas bsupply.(1,1'mbstantially as shown and described and fortlie purpose specified. y

In testimony whereof I have hereunto set my hand and afxed my seal in presence of two subscribing Witnesses.

FRANKLIN P. MILLER. [L. s]

Vitnesses:

BENJ. F. MILLER, ADELAIDE L. MILLER. 

